¿Presencia del español en el paisaje urbano de Washington D.F.? Un estudio del paisaje lingüístico mediado por Internet

Objetivo de esta comunicación es presentar los resultados sobre un análisis realizado en torno a lo que podemos denominar el «paisaje lingüístico hispano virtual» en Washington D.F. Los estudios sobre paisaje lingüístico han experimentado en el último tiempo un verdadero boom, sobre todo como reflejo de la convivencia de diferentes culturas con sus respectivas lenguas y variedades en las urbes del siglo XXI. En efecto: el paisaje lingüístico multilingüe es uno de los aspectos más explotados en trabajos en esta línea teórica. En este estudio el centro de atención no es el paisaje "real", documentado in situ y captado motu propio en instantáneas por nuestros aparatos fotográficos, sino el paisaje lingüístico mediatizado por el ordenador y difundido mediante la World Wide Web. En este sentido, lo que nos interesa es si se ve reflejada y qué manera la hispanidad en Washington D.F. a través del paisaje urbano que nos ofrecen programas especializados como Google Earth y Google Street View. Con este objetivo proponemos un paseo virtual por Washington D.F. y sus diferentes barrios para analizar mediante un estudio de naturaleza cuantitativa y cualitativa, apoyándonos en las herramientas teóricas y metodológicas que ofrecen los estudios de paisaje lingüístico y de la Comunicación Mediada por Ordenadores, de qué manera lo hispano constituye un engranaje del paisaje lingüístico de esta ciudad.

Cellular senescence of white blood cells in very long-term survivors after allogeneic hematopoietic stem cell transplantation: the role of chronic graft-versus-host disease and female donor sex

In this single-center, cross-sectional study, we evaluated 44 very long-term survivors with a median follow-up of 17.5 years (range, 11-26 years) after hematopoietic stem cell transplantation. We assessed the telomere length difference in human leukocyte antigen-identical donor and recipient sibling pairs and searched for its relationship with clinical factors. The telomere length (in kb, mean +/- SD) was significantly shorter in all recipient blood cells compared with their donors' blood cells (P < .01): granulocytes (6.5 +/- 0.9 vs 7.1 +/- 0.9), naive/memory T cells (5.7 +/- 1.2 vs 6.6 +/- 1.2; 5.2 +/- 1.0 vs 5.7 +/- 0.9), B cells (7.1 +/- 1.1 vs 7.8 +/- 1.1), and natural killer/natural killer T cells (4.8 +/- 1.0 vs 5.6 +/- 1.3). Chronic graft-versus-host disease (P < .04) and a female donor (P < .04) were associated with a greater difference in telomere length between donor and recipient. Critically short telomeres have been described in degenerative diseases and secondary malignancies. If this hypothesis can be confirmed, identification of recipients at risk for cellular senescence could become part of monitoring long-term survivors after hematopoietic stem cell transplantation.

Fetuin-A and cystatin C are endogenous inhibitors of human meprin metalloproteases

Meprin and , zinc metalloproteinases, play significant roles in inflammation, including inflammatory bowel disease (IBD), possibly by activating cytokines, like interleukin 1 , interleukin 18, or tumor growth factor . Although a number of potential activators for meprins are known, no endogenous inhibitors have been identified. In this work, we analyzed the inhibitory potential of human plasma and identified bovine fetuin-A as an endogenous meprin inhibitor with a K(i) (inhibition constant) of 4.2 × 10(-5) M for meprin and a K(i) of 1.1 × 10(-6) M meprin . This correlated with data obtained for a fetuin-A homologue from carp (nephrosin inhibitor) that revealed a potent meprin and inhibition (residual activities of 27 and 22%, respectively) at a carp fetuin concentration of 1.5 × 10(-6) M. Human fetuin-A is a negative acute phase protein involved in inflammatory diseases, thus being a potential physiological regulator of meprin activity. We report kinetic studies of fetuin-A with the proteolytic enzymes astacin, LAST, LAST_MAM, trypsin, and chymotrypsin, indeed demonstrating that fetuin-A is a broad-range protease inhibitor. Fetuin-A inhibition of meprin activity was 40 times weaker than that of meprin activity. Therefore, we tested cystatin C, a protein structurally closely related to fetuin-A. Indeed, cystatin C was an inhibitor for human meprin (K(i) = 8.5 × 10(-6) M) but, interestingly, not for meprin . Thus, the identification of fetuin-A and cystatin C as endogenous proteolytic regulators of meprin activity broadens our understanding of the proteolytic network in plasma.